Maintain a nutrition and hydration schedule ahead of the marathon to know how your body will react on race day. Or your performance may suffer.

2. Stay Hydrated

The most important nutrient is water.

Athletic performance can decrease if as little as 2 percent body weight is lost.

To stay hydrated, follow these fluid-replacement strategies:

Before Exercise: Consume 16-20 ounces of water and two hours prior to exercise and 7-10 ounces of water 10-20 minutes prior to exercise.

During Exercise: Consume 6-8 ounces of water every 15-20 minutes. If you exercise for more than an hour, consume a sports drink containing 4-8 percent of carbohydrates, which will energize working muscles.

After Exercise: 24 ounces of fluid should be consumed for every pound of water lost during exercise.

3. Maintain Carb Fix

Maximizes muscle glycogen stores before race day to improve performance and maintain a high-intensity performance.